I used to have a Hugo1. As far as I remember all the headphone outputs and the RCA are all equally connected so you can use any of them as outputs to headphones or an amp. If you want RCA out to an amplifier why don't you just use a pair of RCA to RCA cables? I am a bit confused about how you want to use your existing 3.5mm>>RCA cable. Surely you can lug the jack into the hugo and then the RCA into your amp. If you want to use it the other way around I am sure it will be fine as well. )Although the 3.5mm>>RCA cable you have may have a directional arrow on it, it should work equally well the other way around - in fact I really can't see why it wouldn't).